/* tools/mkbootimg/bootimg.h
**
** Copyright 2007, The Android Open Source Project
**
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
**
**     http://www.apache.org/licenses/LICENSE-2.0
**
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*/

#ifndef _BOOT_IMAGE_H_
#define _BOOT_IMAGE_H_

typedef struct boot_img_hdr boot_img_hdr;

#define BOOT_MAGIC "ANDROID!"
#define BOOT_MAGIC_SIZE 8
#define BOOT_NAME_SIZE 16
#define BOOT_ARGS_SIZE 512

#define KERNL_PAGE_SIZE 2048
#define BOOT_EXTRA_ARGS_SIZE  1024

struct boot_img_hdr
{
    unsigned char magic[BOOT_MAGIC_SIZE];

    unsigned kernel_size;  /* size in bytes */
    unsigned kernel_addr;  /* physical load addr */

    unsigned ramdisk_size; /* size in bytes */
    unsigned ramdisk_addr; /* physical load addr */

    unsigned second_size;  /* size in bytes */
    unsigned second_addr;  /* physical load addr */

    unsigned tags_addr;    /* physical addr for kernel tags */
    unsigned page_size;    /* flash page size we assume */
    union{
    	unsigned dt_size;      /* device tree in bytes */
	unsigned header_version;
    };
    /* operating system version and security patch level; for
     * version "A.B.C" and patch level "Y-M-D":
     * ver = A << 14 | B << 7 | C         (7 bits for each of A, B, C)
     * lvl = ((Y - 2000) & 127) << 4 | M  (7 bits for Y, 4 bits for M)
     * os_version = ver << 11 | lvl */
    unsigned os_version;
    unsigned char name[BOOT_NAME_SIZE]; /* asciiz product name */

    unsigned char cmdline[BOOT_ARGS_SIZE];

    unsigned id[8]; /* timestamp / checksum / sha1 / etc */
	/* Supplemental command line data; kept here to maintain
     * binary compatibility with older versions of mkbootimg */
    uint8_t extra_cmdline[BOOT_EXTRA_ARGS_SIZE];
};

/*
** +-----------------+
** | boot header     | 1 page
** +-----------------+
** | kernel          | n pages
** +-----------------+
** | ramdisk         | m pages
** +-----------------+
** | second stage    | o pages
** +-----------------+
** | device tree     | p pages
** +-----------------+
**
** n = (kernel_size + page_size - 1) / page_size
** m = (ramdisk_size + page_size - 1) / page_size
** o = (second_size + page_size - 1) / page_size
** p = (dt_size + page_size - 1) / page_size
**
** 0. all entities are page_size aligned in flash
** 1. kernel and ramdisk are required (size != 0)
** 2. second is optional (second_size == 0 -> no second)
** 3. load each element (kernel, ramdisk, second) at
**    the specified physical address (kernel_addr, etc)
** 4. prepare tags at tag_addr.  kernel_args[] is
**    appended to the kernel commandline in the tags.
** 5. r0 = 0, r1 = MACHINE_TYPE, r2 = tags_addr
** 6. if second_size != 0: jump to second_addr
**    else: jump to kernel_addr
*/
#define BOOT_HEADER_VERSION_ONE 1
struct boot_img_hdr_v1 {
    uint32_t recovery_dtbo_size;   /* size in bytes for recovery DTBO image */
    uint64_t recovery_dtbo_offset; /* offset to recovery dtbo in boot image */
    uint32_t header_size;
} __attribute__((packed));

/* When the boot image header has a version of 2, the structure of the boot
 * image is as follows:
 *
 * +---------------------+
 * | boot header         | 1 page
 * +---------------------+
 * | kernel              | n pages
 * +---------------------+
 * | ramdisk             | m pages
 * +---------------------+
 * | second stage        | o pages
 * +---------------------+
 * | recovery dtbo/acpio | p pages
 * +---------------------+
 * | dtb                 | q pages
 * +---------------------+

 * n = (kernel_size + page_size - 1) / page_size
 * m = (ramdisk_size + page_size - 1) / page_size
 * o = (second_size + page_size - 1) / page_size
 * p = (recovery_dtbo_size + page_size - 1) / page_size
 * q = (dtb_size + page_size - 1) / page_size
 *
 * 0. all entities are page_size aligned in flash
 * 1. kernel, ramdisk and DTB are required (size != 0)
 * 2. recovery_dtbo/recovery_acpio is required for recovery.img in non-A/B
 *    devices(recovery_dtbo_size != 0)
 * 3. second is optional (second_size == 0 -> no second)
 * 4. load each element (kernel, ramdisk, second, dtb) at
 *    the specified physical address (kernel_addr, etc)
 * 5. If booting to recovery mode in a non-A/B device, extract recovery
 *    dtbo/acpio and apply the correct set of overlays on the base device tree
 *    depending on the hardware/product revision.
 * 6. prepare tags at tag_addr.  kernel_args[] is
 *    appended to the kernel commandline in the tags.
 * 7. r0 = 0, r1 = MACHINE_TYPE, r2 = tags_addr
 * 8. if second_size != 0: jump to second_addr
 *    else: jump to kernel_addr
 */

#define BOOT_HEADER_VERSION_TWO 2

struct boot_img_hdr_v2/* : public boot_img_hdr_v1 */ {
    uint32_t dtb_size; /* size in bytes for DTB image */
    uint64_t dtb_addr; /* physical load address for DTB image */
} __attribute__((packed));

#endif
